Effects of anterior hypothalamic deafferentation on LH, FSH, prolactin and sexual behavior in the ovariectomized ewe.

PIP: The effects of anterior hypothalamic deafferentation on luteinizing hormone (LH), follicle stimulating hormone (FSH), prolactin (PRL), and sexual behavior in the ovariectomized ewe was investigated. Response to injection of estradiol benzoate (50 mcg) was measured before and after surgery. In all 4 cases the estradiol-induced release of LH and PRL observed prior to surgery was eliminated after deafferentation. FSH and basal-PRL levels were also affected. After 3 months, 2 ewes showed partial recovery. Sexual behavior was eliminated in 2 cases. In the ewe, the anterior dorsal inputs from the preoptic anterior hypothalamus are required for the positive feedback of estrogens on LH and maintenance of FSH levels.^ieng